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Diffstat (limited to 'roms/u-boot/doc/README.fsl-trustzone-components')
| -rw-r--r-- | roms/u-boot/doc/README.fsl-trustzone-components | 25 |
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diff --git a/roms/u-boot/doc/README.fsl-trustzone-components b/roms/u-boot/doc/README.fsl-trustzone-components new file mode 100644 index 000000000..e1223469e --- /dev/null +++ b/roms/u-boot/doc/README.fsl-trustzone-components @@ -0,0 +1,25 @@ +Freescale ARM64 SoCs like LS2080A have ARM TrustZone components like +TZPC-BP147 (TrustZone Protection Controller) and TZASC-400 (TrustZone +Address Space Controller). + +While most of the configuration related programming of these peripherals +is left to a root-of-trust security software layer (running in EL3 +privilege mode), but still some configurations of these peripherals +might be required while the bootloader is executing in EL3 privilege +mode. The following sections define how to turn on these features for +LS2080A like SoCs. + +TZPC-BP147 (TrustZone Protection Controller) +============================================ +- Depends on CONFIG_FSL_TZPC_BP147 configuration flag. +- Separates Secure World and Normal World on-chip RAM (OCRAM) spaces. +- Provides a programming model to set access control policy via the TZPC + TZDECPROT Registers. + +TZASC-400 (TrustZone Address Space Controller) +============================================== +- Depends on CONFIG_FSL_TZASC_400 configuration flag. +- Separates Secure World and Normal World external memory spaces for bus masters + such as processors and DMA-equipped peripherals. +- Supports 8 fully programmable address regions, initially inactive at reset, + and one base region, always active, that covers the remaining address space. |